Goals: The conference, "Substance Abuse: New Approaches to Understanding and Treatment," will provide a state of the art view of important new directions in substance abuse by examining the biology of addiction, new advances in research, and new advances being made in the treatment of addiction. Attendees will gain an understanding of the brain mechanisms that are of particular importance for studies of addiction and that are emerging as relevant for clinical research and treatment. Through publication in "Clinical Neuroscience Research," the proceedings will continue the active tradition of the Association for Research in Nervous and Mental Disease in providing information critical to future research and clinical care to a wider audience. Organization: The one and a half day conference has been organized as a series of fifteen talks by invited speakers to cover topics beginning with the epidemiology of substance abuse, genetics of addictive disorders, gender differences in response to abuse, animal models and update of receptors involved in addictive disorders. The conference will then touch on the different areas of abuse and their treatments - stimulant addiction, nicotine addiction, cannaboid use, alcoholism, and opiate addiction. Each session is to be followed by audience participation in a discussion led by the session chairman. The conference format is consistent each year. Participants: Researchers among the most active in their respective fields have been chose to speak by the organizers of the conference, Drs. Charles O'Brien, Chris Evans, Eric Nestler, Nora Volkow and Jack Barchas. (cf. Appendix)